% abstract
\newenvironment*{abstract}[2]{
	%\parindent{2em}
    \def\invalue{#1}
    \def\english{e}
    \def\keywords{#2}
    % 论文题目
    \begin{center}
        \ifx\invalue\english
        	{\Large \bfseries \@etitle} \\
        	\vspace{1.5em}
            {\LARGE \bfseries Abstract} \\
			\addcontentsline{toc}{chapter}{Abstract}
        \else
		    {\Large \bfseries \@title} \\
        	\vspace{1.5em}
            {\LARGE \bfseries 摘~~~~要} \\
			\addcontentsline{toc}{chapter}{摘要}
        \fi
        \vspace{0.5em}
    \end{center}
}{
	\par
	\vspace{1cm}
	\noindent
	\ifx\invalue\english
		{\bfseries Key Words: }
	\else
		{\bfseries 关键词： }
	\fi
	\keywords
	\cleardoublepage
}